Master's MateSafety Initiative Network
The Master's Mate Safety Initiative Network (MMSIn) — like AAA for the ocean, but free & community-driven. Cruisers keeping each other safe: anchor-drag & distress alerts, a verified captains directory, and a watch network that has your back.
Passenger (Inspected)
SEA OTTER IV
MMSI 366886710 · Call sign WDB3402
Not yet on Master's MateType
Passenger (Inspected)
Flag
USALength
13.7 m
Beam
4.6 m
Draft
2.3 m
Call sign
WDB3402
Official No.
930902
Hull ID
AEC45019D888
AIS reports
1
SEA OTTER IV, a ferry flagged in the United States, measures 13.7 metres on deck. SEA OTTER IV has a 4.6 m beam and a 2.3-metre draft. She's on record as MMSI 366886710, call sign WDB3402. Bring SEA OTTER IV aboard the Master's Mate Safety Initiative Network — free, and every captain on it has the others' backs.
Free forever · No credit card · for passenger & charter operators
Keep every soul aboard SEA OTTER IV safe.
Distress alerting, live AIS, onboard monitoring and weather routing — the safety stack for boats that carry people.
Switch on the safety stack — free →Takes 60 seconds · Your data stays yours · Built by cruisers, for cruisers
Wherever SEA OTTER IV roams, you're never out there alone.
Thousands of cruisers on the Master's Mate Network — ready to help the moment something goes wrong.
Free with your claim · for passenger & charter operators
The most powerful cruising platform ever built — yours, free.
Joining the Safety Initiative Network doesn't just put SEA OTTER IV on the map. It hands you the full bridge:
Distress Mesh
Mayday & Pan-Pan that ripple out to nearby cruisers — a watch network that has your back.
Live AIS & Traffic
See every vessel around you in real time. Closest-approach warnings before they matter.
Systems Monitoring
Batteries, bilge, tanks, Victron & NMEA 2000 telemetry — your whole boat on one dashboard.
Weather & Routing
GRIB wind, swell & current on the chart. Plan passages with ETA-calibrated forecasts per leg.
Anchor Watch
GPS-precise drag alarms that actually wake you — and your whole crew. Sleep through the night.
Worldwide Charts
Navionics-grade vector charts, satellite & raster overlays, online or off. Your whole cruising ground.
Onboard Cameras
Watch your boat from anywhere — live feeds and 24h recording, straight from your gateway.
Hail Any Captain
A verified captains directory + direct hailing. Reach the boat next to you, or across the bay.
Claim SEA OTTER IV and switch it all on
Free to join · nothing to install to start · cancel anytime
About SEA OTTER IV
What kind of vessel is SEA OTTER IV?
SEA OTTER IV is a Passenger (Inspected) flagged to United States of America.
What is SEA OTTER IV's MMSI?
SEA OTTER IV's MMSI is 366886710. Call sign WDB3402.
How big is SEA OTTER IV?
SEA OTTER IV is about 13.7 m long, 4.6 m on the beam, drawing 2.3 m.
Is SEA OTTER IV on the Master's Mate Safety Initiative Network?
Not yet. If SEA OTTER IV is your boat, you can claim it free and join the Master's Mate Safety Initiative Network (MMSIn).
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